Managing big meltdowns

I agree with Grandmabatty, it’s not about attention seeking. I had similar problems with my dgd when she was younger and had to leave her alone until she was ready then cuddle and soothe before distracting with an activity.

Small children have big emotions which they can't self regulate. He absolutely is not doing it for attention. My dgs2 has had meltdowns all his wee life. It could also be separation anxiety. While he's in the throes of it, he won't be able to respond to you. I would try to distract him before it starts. Praise him for good behaviour when you can. Ask him if he's ready to talk. Cuddle him if he allows it..Now dgs2 is slightly older, I tell him to go to another room till he feels calm.

I'd say give him a little reasonable comfort, then leave him to get on with it: be there in a chair and wait it out, and he can always come for a cuddle?

He wants attention so if you give it to him you are rewarding bad behaviour. Difficult as it is you should walk off and leave him. Its called tough love.